Dialkoxyphosphonalkyl derivatives of cyclicureides containing glycidyl groups

ABSTRACT

1-Glycidyl-3-dialkoxyphosphonoalkyl-hydantoins and 1-glycidyl-3dialkoxyphosphonoalkyl-dihydrouracils. These compounds are used as flame-retardant additives in plastics, especially as additives to epoxide resins.

x1 2 ma ma s35 United S Porret et al.

DIALKOXYPHOSPHONALKYL DERIVATIVES OF CYCLICUREIDES CONTAINING GLYCIDYL GROUPS Inventors: Daniel Porret, Binningen; Jiirgen Habermeier, Pfeffingen, both of Switzerland Ciba-Geigy Corporation, Ardsley, NY.

Filed: Dec. 7, 1973 Appl. No.: 423,363

Assignee:

Foreign Application Priority Data Dec. 12, 1972 Switzerland 18031/72 US. Cl. 260/309.5; 106/15 FP; 260/2 P Int. Cl. C07D 49/34 Field of Search 260/309.5, 2 EP References Cited UNITED STATES PATENTS 6/1969 Porret et a1 260/309.5

Primary ExaminerEthel G. Love Attorney, Agent, or Firm-Vincent J. Cavalieri; Nestor W. Shust 1 5 7] ABSTRACT 1-G1ycidyl-3-dialkoxyphosphonoalkyl-hydantoins and l-glycidyl-3-dia1koxyphos@onoa1ky1-dihydrouracils These compounds fie fi sed as flame-retardant additives in plastics, especially as additives to epoxide res- 7 Claims, No Drawings DIALKOXYPHOSPHONALKYL DERIVATIVES OF CYCLICUREIDES CONTAINING GLYCIDYL GROUPS The invention relates to 1-glycidyl-3-dialkoxyphosphonoalkyl-hydantoins and l-glycidyl-3-dialkoxyphosphonoalkyl dihydrouracils, a process for their manufacture and their use as flame-retardant additives in plasl tics, especially as additives to epoxide resins.

Flame-retardant agents containing phosphorus are already known. To achieve a favourable effect, considerable quantities of these agents, in most cases more than must be added to the plastics to be protected, but this frequently has an unfavourable effect in other respects, for example mechanical respects, on the protected plastics. It has now been found that the compounds containing phosphorus, according to the invention, render plastics noninflammable if they are added to the plastics in such amounts that the phosphorus content is at least 0.8 4%.

The compounds containing phosphorus, according to the invention, are reactive because of their glycidyl group and after being added to the epoxide resin/curing agent mixtures are built into the polymeric lattice during curing, so that even when used in larger amounts they do not impair the good properties of the cured plastics.

The compounds can above all be employed with advantage in the electrical and electronics field.

The compounds correspond to the formula I in which Z denotes a nitrogen-free divalent radical which is required to completea five-membered or sixmembered ring, A denotes an alkylene group with 1 -12 carbon atoms which is optionally interrupted by oxygen atoms and R, and R each denote an alkyl or alkenyl group which can be substituted, for example by halogen, or together denote an alkylene group with two to five carbon atoms.

Z preferably represents a methylene group which can be substituted by alkyl groups with one to six carbon atoms, or a cycloalkylene group, such as the methylene group or especially the propylidene-(2,2) group, and also the nor iso-propylmethylene group, the cyclohexylidene group or cyclopentylidene group, or an ethylene group which is optionally substituted by alkyl groups of one to four carbon atoms, such as the ethylene, 1,2-dimethylethylene, 2,2-dimethylethylene or 1- methyl-2-isopropyl-ethylene group.

A preferably denotes an alkylene group with two to six carbon atoms, especially the ethylene group, or the radical of a diethyl ether.

R and R preferably each denote an alkyl or alkenyl group with one to four carbon atoms, especially the methyl or ethyl group, but also the propyl, butyl, aliyl, butenyl or monochloroethyl group.

The new compounds are manufactured according to known processes by glycidylation of the corresponding 3-dialkylphosphonomethyl-hydantoins or 3-dialkyl- 2 phosphonomethyl dihydrouracils. The procedure followed is that ina compound of the formula II in which X denotes a radical which can be converted into the 1,2-epoxyethyl group, this radical is converted into the epoxyethyl group.

A radical X which can be converted into the 1,2- epoxyethyl radical is above all a hydroxy-halogenoethyl radical which carries the functional groups on different carbon atoms, especially a 2-halogeno-l-hydroxyethyl radical. Halogen atoms are here especially chlorine atoms or bromine atoms. The reaction takes place in the customary manner, above all in the presence of agents which split off hydrogen halide, such as strong alkalis, for example anhydrous sodium hydroxide or aqueous sodium hydroxide solutions. However, it is also possible to use other strongly alkaline reagents, such as potassium hydroxide, barium hydroxide, calcium hydroxide, sodium carbonate or potassium carbonate.

A further radical X which can be converted into the 1,2-epoxyethyl radical is, for example, the ethenyl radical, which can be converted into the 1,2-epoxyethyl radical in a known manner by means of per-compounds, such as, above all, by reaction with hydrogen peroxide or per-acids, for example peracetic acid, perbenzoic acid or monoperphthalic acid.

The starting substances of the formula II are obtained in a manner which is in itself known. Thus it is possible to react a compound of the formula III (III) under mild conditions with a compound of the formula X-CH Hal, wherein Hal represents a halogen atom and X has the abovementioned meaning. Preferably, the compound of the formula III is reacted with an epihalogenohydrin, above all epihalogenohydrin, in the presence of a catalyst, such as, in particular, a tertiary amine, a quaternary ammonium base or a quaternary ammonium hydroxide.

The compounds of the formula [II can be obtained by reacting a compound of the formula IV as YA NH (IV) wherein Y denotes chlorine or bromine, with a trialkylphosphite of the formula V wherein R denotes an optionally substituted alkyl or alkenyl group.

For bringing about the reaction, which corresponds to a Michaelis-Arbusow reaction, the mixture is usually warmed over the course of several hours to above 100C, preferably 120 160C, in the course of which RY, that is to say, for example, methyl chloride, ethyl chloride, butyl chloride or 1,2-dichloroethane, distils off.

The compounds of the formula IV are obtained by reaction of the corresponding hydantoins or dihydrouracils which are unsubstituted in the 3-position, with a compound of the formula VI Hal-AHal wherein Hal denotes chlorine or bromine, in the pres ence of agents which split off hydrogen halide, such as alkalis or strongly basic salts, for example sodium carbonate. Examples of compounds of the formula Vi are B, ,B-dichloroethane or B, B'-dichlorodiethy1 ether.

The products according to the invention are liquid to viscous substances which are colourless in the pure state. They can be purified by vacuum distillation.

The new substances are very suitable for use as additives to customary epoxide resins to render them noninflammable or flame'retardant. For this purpose they have the advantage of a low viscosity in most cases, so that they simultaneously exert a certain action as a re active diluent.

The parts the examples which follow denote parts by weight.

EXAMPLES 1. l-Glycidyl-3-(dimethoxyphosphonoethyl)-5,S-dimethylhydantoin a. 3-(B-Chloroethyl)-5,S-dimethyl-hydantoin A mixture of 1,664 g .of 5,5-dimethylhydantoin (13.0 mols), 897 g of anhydrous potassium carbonate (6.5 mols), 5,148 g of 1,2-dichloroethane (52 mols) and 1,458 ml of dimethylformamide is reacted for 18 hours and 20 minutes at 90C to 100C internal temperature (external temperature 155C), whilst constantly removing the resulting water of reaction by azeotropic circulatory distillation. Water of reaction eliminated: l g (94.0% of theory). Thereafter the reaction mixture, whilst still hot, is separated by filtration from the potassium chloride produced, the filtrate concentrated on a rotary evaporator at 100C and the residue is dried to constant weight at 100C and 10 mm Hg.

2,385 g of a clear brown, highly viscous substance (96.2% of theory) are obtained.

The crude product is distilled at 0.1 to 0.2 mm Hg and 146 149C: Yield of pure substance, 2,068.3 g (83.4% of theory). A sample recrystallised from methanol melts at 958 to 962C and has the following analytical data:

b. 3-( Dimethoxyphosphonoethyl )-5 ,5-dimethylhydantoin A mixture of 381.3 g of 3-(2'-chloroethyl)-5,5- dimethyl-hydantoin (2.0 mols) and 322.6 g of trimethyl phosphite (2.6 mols) is reacted at 120C (hath temperature 180C). The methyl chloride produced in the reaction is condensed in a cold trap at C, for the pur pose of following the course of the reaction. After 39 hours the reaction has ended, the internal temperature has at that point risen to 190C, and 96.7 g of methyl chloride (95.7% of theory) are obtained. The reaction product is freed of readily volatile constituents in a waterpump vacuum at 1 10C and is then dried to constant weight at 10 mm Hg and C.

490 g of a yellowish, clear, highly viscous crude product (92.7% of theory) are obtained, showing the following analytical data: 9.80% of phosphorus and s 0.2% of chlorine.

A crude product purified by distillation in a bulb tube (at C external temperature and 10" mm Hg) and subsequent crystallisation from ethyl acetate melts at 10l.2 102.6C.

The H-NMR spectrum can be reconciled with the following structure:

c. 1-Glycidyl-3-(dimethoxyphosphonoethyl )-5 ,5- dimethyl-hydantoin A mixture of 132.1 g of 3-(dimethoxyphosphonoethyl)-5,S-dimethyl-hydantoin (0.5 mol), 463 g of epichlorohydrin (5.0 mols) and 0.5 g of tetramethylammonium chloride is stirred for 100 minutes at 118C. The mixture is then cooled to 60C; 44 g of 50% strength sodium hydroxide solution (0.55 mol) are added dropwise over the course of 3 hours with vigorous stirring, under a waterpump vacuum; at the same time the water present in the reaction mixture is removed continuously by azeotropic circulatory distillation. To complete the reaction, distillation is continued for a further 30 minutes after the dropwise addition; the mixture is then cooled to 20C, the sodium chloride which has precipitated is filtered off and the epichlorohydrin solution is concentrated on a rotary evaporator under a waterpump vacuum. The product is then dried to constant weight at 100C and 10" mm Hg.

143.3 g (89.5% of theory) of a yellow, clear, viscous resin are obtained, of which the epoxide content is 3.07 epoxide equivalents/kg (98.4% of theory). The product contains 0.8% of chlorine and 7.54% of phosphorus (theory 9.67% P).

2. l-Glycidyl-3-(diethoxyphosphono-n-butyl )-5 ,5 dimethyl-hydantoin a. 3-(4-Chlorobutyl)-5,5-dimethyl-hydantoin A mixture of 538 g of 5,5-dimethyl'hydantoin (4.2 mols), 290 g of anhydrous potassium carbonate (2.1 mols) .and 2,130 g of 1,4-dichlorobutane (16.77 mols) Analytical data: Found: Calculated:

49.26% C 49.43% C 7.02% H 6.91% H 13.1%N 12.81%N 15.72% Cl 16.21% Cl b. 3-( Diethoxyphosphono-n-butyl)- ,S-dimethylhydantoin 43.9 g of 3-(4-chloro-n-butyl)-5,S-dimethyl-hydantoin (0.2 mol) and 39.9 g of triethyl phosphite are reacted for 31 hours at 163 to 205C (bath temperature 184 to 220C) in the manner described under Example 1 b, ethyl chloride being split off. The mixture is worked up analogously to Example 1 b and 60.1 g of a clear, yellow, viscous substance are obtained (93.9% of theory). Analytical data: 8.95% P, 0.3% chlorine. Distillation in a bulb tube (external temperature: 140 160C and 0.03 mm Hg) gives a clear, colourless, viscous distillate which displays the following analytical data:

c. 1 -Glycidyl-3-( diethoxyphosphono-n-butyl)-5 ,5- dimethyl-hydantoin 48.1 g of 3-(diethoxyphosphono-n-butyl)-5,5- dimethyl-hydantoin (0.15 mol), 139 g of epichlorohydrin (1.5 mols) and'0.15 g of tetramethylammonium chloride are stirred for 90 minutes at 1 118C, in the manner described under Example 1 c. The solution is then cooled to 60C and 13.2 g of 50% strength aqueous sodium hydroxide solution are added dropwise over the course of 3 hours. The water is constantly removed by azeotropic circulatory distillation. After a further 30 minutes, the reaction is complete, and the mixture is worked up as described under Example 1 c. 38.4 g of a clear, yellow, viscous resin (68% of theory) are obtained, having an epoxide content of 2.62 epoxide equivalents/kg (98.8% of theory). A vacuum distillation in a bulb tube (external temperature 156 160C, 0.02 mm Hg) gives a clear, colourless, viscous distillate having an epoxide content of 2.66 epoxide equivalents/kg (98.5% of theory).

3. 1-Glycidyl-3-(diethoxyphosphonoethyl)-5-ethy1-5- methyl-hydantoin a. 3-(B-Chloroethyl)-5-ethyl-5-methyl-hydantoin 284.3 g of 5-ethyl-5-methyl-hydantoin (2.0 mols), 138.2 g of anhydrous potassium carbonate (1.0 mol), 791.7 g of 1,2-dichloroethane (8.0 mols) and 230 ml of dimethylformamide are subjected to an azeotropic circulatory distillation for 25 hours at 90C to 107C internal temperature (external temperature: 160C), in the manner described under Example 1 a. After completion of the reaction, the mixture is filtered whilst still hot and the filtrate is concentrated on a rotary evaporator at 90C under a waterpump vacuum. The reaction mixture is then dried to constant Weight at 90C and 10" mm Hg. 392.5 g of a brown, clear, product (95.9% of theory) are obtained, and are purified by vacuum distillation (boiling point 0.2: 147C). Yield of pure product: 327.3 g of theory). A sample recrystallised from diethyl ether melts at 580C to 590C.

Analytical data: Found: Calculated:

47.23% C 46.95% C 6.56% H 6.40% H 13.61% N 13.69% N 17.36% C] 17.32% Cl Elementary analysis: Found: Calculated:

47.15% C 47.06% C 7.79% H 7.57% H 9.22% N 9.15% N 10.04%P 10.11%P

c. 1-Glycidyl-3-(diethoxyphosphonoethyl)-5-ethyl-5- methyl-hydantoin 61.2 g of 3-(diethoxyphosphonoethyl)-5-ethyl-5- methyl-hydantoin (0.2 mol), 277.5 g of epichlorohydrin (3.0 mols) and 0.2 g of tetramethylammonium chloride are stirred for minutes at 1 15 l 19C. The mixture is then cooled to 60C and 17.6 g of 50% strength aqueous sodium hydroxide solution are added dropwise over the course of 4 hours whilst stirring, under a waterpump vacuum. The water present in the mixture is removed by azeotropic circulatory distillation analogously to Example 1 c. The mixture is worked up analogously to Example 1 c and 65.7 g of a yellow, clear, viscous resin (90.6% of theory) having an epoxide content of 2.71 epoxide equivalents/kg (96.7% of theory) are obtained. The product contains 0.65% of chlorine and 6.72% of phosphorus. 4. B-( Dimethoxyphosphono )-B l-glycidyl-S ,5- dimethyl-hydantoin-3-yl)-diethyl ether 11. 3-(3-Oxy-5-chloro-pentyl)-5,S-dimethyl-hydantom Elementary analysis: Found: Calculated:

45.99% C 46.06% C 6.41% H 6.44% H 11.73%N 11.94% N 14.92% Cl 15.11% C] b. B-(Dimethoxyphosphono)-B-(5,5-dimethylhydantoin-3-yl)diethyl ether 70.4 g of ,8-chloro-B(5,5-dimethylhydantoin-3-yl)- diethyl ether (0.3 mol) and 48.4 g of trimethyl phosphite are reacted for 48 hours and 25 minutes at 120C to 189C bath temperature. After 48 hours and 25 minutes the reaction is complete and 14.9 g of methyl chloride (98.3% of theory) have been eliminated. The mixture is worked up analogously to Example 1 b and 84.3 g of a clear, yellow, viscous product (91.1% of theory) are obtained, displaying the following analytical data: 8.70% of phosphorus and 0.3% of chlorine.

c. /3-( Dimethoxyphosphono)-,8"( 1-glycidyl-5,5- dimethyl-hydantoin-3-yl)-diethyl ether 67.0 g of B-(dimethoxyphosphono)-,8-(5,5-dimethyl-hydantoin-3-yl)'diethyl ether (0.217 mol), 201 g of epichlorohydrin (2.17 mols) and 0.2 g of tetramethylammonium chloride are stirred for 90 minutes at 116 118C. The mixture is then cooled to 60C, 19 g of 50% strength aqueous sodium hydroxide solution are added dropwise over the course of 3 hours and minutes, and the water is removed by azeotropic circulatory distillation. The mixture is worked up analogously to Example 1 c and 48 g of a yellow, viscous resin (60.7% of theory) are obtained, having an epoxide content of 2.47 epoxide equivalents/kg (90.2% of theory). Phosphorus content: 6.8%. 5. l-Glycidyl-3-(diethoxyphosphonoethyl)-5,S-dimetlr yl-hydantoin a. 3(Diethoxyphosphonoethyl)-5,5dimethyl-hydantoin 704.1 g of 3-(2-chloroethyl)-5,S-dimethyl-hydantoin (3.0 mols) [manufactured according to Example 1a] and 598.5 g of triethyl phosphite are stirred at 162 to 188C. The elimination of ethyl chloride is complete after 22 hours and minutes and the reaction product is worked up analogously to Example 1 b. 859.8 g of a yellow, clear, viscous substance (98.0% of theory) are obtained, having a phosphorus content of 8.6%.

b. 1-Glycidyl-3-(diethoxyphosphonoethyl)-5,5- dimethyl-hydantoin A mixture of 146.1 g of 3-(diethoxyphosphonoethyl)-5,5-dimethyl-hydantoin (0.5 mol), 694 g of epi chlorohydrin (7.5 mols) and 0.5 g of tetramethylammonium chloride is stirred for 105 minutes at 105C.

44 g of 50% strength aqueous sodium hydroxide solution are added dropwise over the course of 3 hours at 60C, analogously to Example 1 c). The mixture is worked up analogously to Example 1 c) and 157 g of a yellow, clear resin (90.2% of theory) with 2.74 epoxide equivalents/kg (95.5% of theory) and a phosphorus content of 6.13% are obtained. 6. 1-Glycidyl-3-(dimethoxyphosphonoethyl)-5,5-pentamethylene-hydantoin a. 3-(B-Chloroethyl)-5,S-pentamethylene-hydantoin 336.4 g of5,5-pentamethylene-hydantoin (2.0 mols), 138.2 g of anhydrous potassium carbonate (1.0 mol), 791.7 g of 1,2-dichloroethane (8.0 mols) and 300 ml of dimethylformamide are reacted as described under Example l a). After a reaction time of 21% hours at 101C to l 17C internal temperature (external temperature C) the reaction is complete and the reaction mixture is filtered whilst still hot. The filtrate is worked up analogously to Example 1 a). 460.8 g ofa brownish, crystalline product, (99.86% of theory) having a melting point of 154C to 156.4C are obtained. Recrystallisation of the crude product from toluene in the ratio of 1:1.6 gives the pure compound, of melting point 156 to 158C, in 86% yield.

Found: Calculated:

51.83% C 52.06% C 6.67% H 6.55% H 12.27% N 12.14% N 15.11% Cl 15.37% C1 b. 3-(Dimethoxyphosphonoethyl)-5,S-pentamethylene-hydantoin 48.4 g of trimethyl phosphite (0.39 mol) are added dropwise over the course of 115 minutes to 69.3 g of 3-(B-chloroethyl)-5,5-pentamethylene-hydantoin (0.3 mol) at C. After 20 hours and 45 minutes, the elimination of methyl chloride has ceased. The reaction mixture is worked up as described in Example 1 b and 84.3 g of a solid, yellow product (92.3% of theory) containing 8.9% of phosphorus and 0.3% of chlorine are obtained.

6. 1Glycidyl-3-(dimethoxyphosphonoethyl )-5 ,5 pentamethylene-hydantoin 60.8 g of -3(dimethoxyphosphonoethyl)-5,5-pentamethylene-hydantoin (0.2 mol), 277.5 g of epichlorohydrin (3.0 mols) and 0.2 g of tetramethylammonium chloride are stirred for 90 minutes at 116 120C. Thereafter, the mixture is cooled to 60C and 17.6 g of 50% strength aqueous sodium hydroxide soluhours/150C. Mouldings having the following proper- 9 tion are added dropwise over the course of 3 hours, analogously to Example 1 c. The mixture is worked up analogously to Example 1 c and 54.3 g of a brown, clear, viscous resin (75% of theory) having an epoxide content of 1.84 epoxide equivalents/kg are obtained.

USE EXAMPLES A mixture, containing 2.41% of phosphorus, of 120 parts of the product manufactured according to Example l, 143 parts of hexahydrophthalic anhydride and 143 parts of an industrially manufactured triglycidyl compound from 1,3-bis-(5,5'-dimethyl-hydantoin-3- yl)-propan-2-ol, containing 6.1 epoxide equivalents/kg, is converted to a clear, homogeneous liquid at 100C and poured into a prewarmed aluminium mould.

Curing takes place in 2 hours/120C 16 ties are obtained:

lnflarnmability: (CTM20*) Level l/Z" Heat distortion point according to Martens (DIN): 103C 11.0-14.0 cm kg/cm 10.5-15.8 kg/mm 4.6 mm

lmpact strength (VSM 77,105) Flexural strength (VSM 77,103) Deflection Water absorption (4 days, 20C) 10 upper edge of the burner and the end face is at a horizontal distance of 1 cm from the lower edge of the burner.

What we claim is: 1. A cyclic ureide containing phosphorus and glycidyl group of the formula R O O wherein Z is methylene, methylene substituted with alkyl groups of one to six carbon atoms, cyclohexylidene, or cyclopentylidene; A is alkylene of one to twelve carbon atoms, or CH CH OCH CH R and R each is alkyl or alkenyl of one to four carbon atoms or R, and R together is alkylene of two to five carbon atoms.

2. A compound according to claim 1 wherein Z is propylidene-(2,2).

3. A compound according to claim 1 wherein R and R each is alkyl or alkenyl of one to four carbon atoms.

4. A compound according to claim 3 wherein R and R is each ethyl or methyl.

5. A compound according to claim 1 wherein A is alkylene of two to six carbon atoms.

6. A compound according to claim 1 wherein A is ethyl.

7. A compound according to claim 1 wherein A is CH CH OCH CH 

1. A CYCLIC UREIDE CONTAINING PHOSPHORUS AND GLYCIDYL GROUP OF THE FORMULA
 2. A compound according to claim 1 wherein Z is propylidene-(2, 2).
 3. A compound according to claim 1 wherein R1 and R2 each is alkyl or alkenyl of one to four carbon atoms.
 4. A compound according to claim 3 wherein R1 and R2 is each ethyl or methyl.
 5. A compound according to claim 1 wherein A is alkylene of two to six carbon atoms.
 6. A compound according to claim 1 wherein A is ethyl.
 7. A compound according to claim 1 wherein A is -CH2CH2OCH2CH2-. 